<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
         div{
            width: 200px;
            height: 200px;
            background-color: red;

            margin-bottom: 10px;
        }

        /* 普通兄弟选择器  ~ */

        .bro ~ div{
            border: 10px double #000;
        }
    </style>
    
</head>
<body>
    <div>
        
    </div>
    
    <div class="bro"> 
       
    </div>

    <div>
        
    </div>

    <div>

    </div>
</body>
</html>